Freeze-dried, aerated dairy or dairy-substitute compositions and methods of making thereof

ABSTRACT

The present invention comprises a freeze-dried, aerated dairy or dairy-substitute composition comprising a dairy or dairy-substitute ingredient and an emulsifier and methods of making thereof.

CROSS REFERENCES TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/599,321, filed Jan. 28, 2010, which is the U.S. national stagedesignation of International Application No. PCT/US08/063312, filed onMay 9, 2008, which claims priority to U.S. application Ser. No.60/916,949, filed on May 9, 2007, the entire contents of which areincorporated herein by reference.

BACKGROUND

Aerated milk compositions, such as aerated yogurt products are known inthe art. Aeration can provide desirable characteristics such as light,fluffy textures. It is also known in the art that aerated products aresubject to physical and chemical instability and therefore candestabilize over time. One solution to such instability issues inaerated milk-based products includes the addition of a hydratedemulsifier to already cultured dairy products before aeration (See e.g.U.S. Pat. No. 7,005,157, hereinafter “the '157 patent”). Specifically,the, 157 patent teaches against adding ingredients directly to the milkblend prior to fermentation because such ingredients can adverselyaffect processing considerations such as fermentation times. The '157patent teaches that the addition of a hydrated emulsifierpost-fermentation avoids adversely lengthening fermentation times whilecontributing to stability. Freeze-drying is a process well known in thefood industry. It is critical in further drying aerated products thatthe resulting product retain sensory attributes that are important toconsumers. Using the invention taught in the '157 patent, hydration ofthe aerated product before freeze-drying can detrimentally affectphysical stability. For example, a hydrated, aerated product when freezedried may result in increased fragility during shipping and handling ofthe product.

As a further example, dissolvability is an important issue in afreeze-dried product. Specifically, the aerated product, which has beendried and treated with air, nitrogen or other gases, must still remainreadily dissolvable upon consumption at such a rate as to transferflavor to the consumer's taste buds. Moreover, the product should bereadily dissolvable to reduce the risk of choking hazards for consumerswith restricted or under-developed oral motor skills or digestivefunctions. As a known solution, increasing the aeration can improvedissolvability. However, increased aeration has the negative effect ofreducing the hardness of the end product. When the hardness is reducedbeyond a certain level, the physical stability of product can becompromised.

Therefore, there is a need for a product that is freeze-dried andaerated that has improved physical stability and improveddissolvability.

SUMMARY

The present invention comprises a freeze-dried, aerated dairy ordairy-substitute composition comprising a dairy or dairy-substituteingredient, an emulsifier, wherein said dairy or dairy-substitutecomposition is pasteurized, and methods of making thereof.

DETAILED DESCRIPTION

As used throughout, ranges are used as a shorthand for describing eachand every value that is within the range. Any value within the range canbe selected as the terminus of the range. When used, the phrase “atleast one of” refers to the selection of anyone member individually orany combination of the members. The conjunction “and” or “or” can beused in the list of members, but the “at least one of” phrase is thecontrolling language. For example, at least one of A, B, and C isshorthand for A alone, B alone, C alone, A and B, B and C, A and C, or Aand Band C.

“Freeze-dry” is a dehydration process that works by freezing thematerial and then reducing the surrounding pressure to allow the frozenwater in the material to sublimate directly from the solid phase to gas.

“Aeration” is the process of introducing air to increase gasconcentration in liquids. Aeration may be performed by bubbling a gasthrough the liquid, spraying the liquid into the gas or agitation of theliquid to increase surface absorption.

“Dissolvability” is defined as the change in hardness of a product ingoing from a dry to a wet state.

“Hardness” is defined as the peak stress prior to fracturing a material.Universal Tester model 4465 with 100 N static load cell, manufactured byInstron in Canton, Mass., is used. The probe used for testing is acompression anvil #2830-011. Initial settings for speed of probe were 1mm/second to approximately 90% compression. Speed based upon journalarticle in J. Texture Studies, 36 (2005), pp 157-173, “Effects of SampleThickness of Bite Force for Raw Carrots and Fish Gels.” Testing isrepeated on 10-15 replicate samples for each variable.

“Viscosity” is defined as a measure of the resistance of a substance toflow. Viscosity is measured using a Brookfield viscometer with aHelipath® stand with an F-T bar before the composition is aerated.Viscosity aids in holding the shape of a substance through aeration anddeposit.

The present invention comprises a dairy or dairy substitute compositionuseful in the preparation of a freeze-dried, aerated product. The firstcomponent of the composition comprises a dairy or dairy substituteingredient. The dairy or dairy substitute ingredient is selected fromany dairy or dairy substitute ingredient ordinarily known in the art.Specifically, the dairy ingredient is selected from the group includingbut not limited to milk, milk powder, yogurt, skim milk and milkproteins and combinations thereof. The dairy substitute ingredient isselected from but not limited to soy proteins and rice proteins andcombinations thereof. The dairy or dairy substitute ingredient ispresent in amount of from 50% to 98%, preferably from 60% to 90% andmost preferably from 70% to 85% of the composition.

The second component of the present composition comprises an emulsifier.While not wishing to be bound by any theories, it is believed that theemulsifier reduces the surface tension at the air-liquid interface,therefore allowing for stable dispersion of air bubbles within theviscous liquid matrix. The emulsifier is preferably a lactylated monoand diglyceride. The lactylated mono and diglyceride is selected fromthe group consisting of but not limited to lactic and citrate acidesters of mono- and diglycerides, distilled mono glycerides, andcombinations thereof. While not wishing to be bound by any theories, itis believed that the lactic acid moiety of the whipping agent resides inthe aqueous phase at the interface of the aqueous phase and thehydrophobic phase while the mono and diglycerides reside in hydrophobicphase of the whipped dairy foam. The lactylated mono and diglyceridesare present in an amount of from 0.001 to 1%, preferably from 0.01 to0.5%, and most preferably from 0.1 to 0.4% of the composition. It isbelieved that the lactylated mono and diglyceride component of thepresent invention promotes stabilization of the final aeratedcomposition.

The combination of the first component and the second component are thenpasteurized through procedures commonly used in the industry.Pasteurization can take between 1 to 10 minutes between 170 F to 210 F,preferably between 180 F to 205 F.

The composition of the present invention can further comprise optionalingredients such as starch, including but not limited to com starch,rice starch (native, physically or chemically modified) and tapiocastarch; sugar/sweetners, stabilizers, flavors, colors, fruit purees,prebiotics, probiotics, vegetable purees, fibers, fortificants such asDHA, minerals and vitamins, and gelatins such as porcine, fish andbovine.

Hardness, Dissolvability and Viscosity

The consumer preference for the final product of the present inventionis believed to be based on physical characteristics such as hardness,viscosity and dissolvability. While each characteristic is important,the correct balance between the three components is desired to optimizethe end product of the present invention. Viscosity is defined as ameasure of the resistance of a substance to flow. Viscosity is measuredusing a Brookfield viscometer with a Helipath® stand with an F-T barbefore the composition is aerated. It is believed that while theviscosity aids in holding the shape of a substance through aeration anddeposit, the hardness aids in physical stability. The dissolvability,also a hardness measurement, is the change in hardness of a product ingoing from a dry to a wet state. With increased aeration, which aids indissolvability, the hardness can be negatively affected. Thecompositions and methods of the present invention have unexpectedlydiscovered the optimum balance between viscosity, hardness anddissovability to provide a physically stable and consumer acceptableproduct.

The composition of the present invention has a hardness value of from0.5 to 8 pounds force, preferably from 1.5 to 5.5 peak load. Peak loadforce can be measured using an Instron Universal Testing Machine fittedwith a 100N load cell anda #2830-011 compression anvil. The traveling isat a speed of 1 mm/sec until initial piece fraction occurs.

The composition of the present invention has a dissolvability in therange of from 0.1 to 8 peak load, preferably from 0.1 to 30 poundsforce.

The composition of the present invention has a viscosity of from 1,000to 150,000 cp, dependent upon the temperature and speed of theviscometer used to measure the viscosity. In the preferred embodiment,the viscosity of the wet composition ranges from 30,000 to 60,000 cp ata 10 RPM speed of the spindle 6 in a Brookfield Viscometer. The mostpreferred range is from 35,000 to 50,000 cp. In an alternate embodiment,the present invention has a viscosity of from 1,000 to 700,000 cp,dependent upon the temperature and speed of the viscometer used tomeasure the viscosity. In the preferred embodiment for the alternateembodiment, the viscosity of the wet composition ranges from 100,000 to400,000 cp at a 5 RPM speed of the spindle 6 in a Brookfield Viscometer.The most preferred range for the alternate embodiment is from 200,000 to350,000 cp. It should be noted that the viscosity can be adjusted basedon the RPM and is dependent upon dissolvability and the stabilizer.

Method of Making

A method of preparing a freeze-dried, aerated, milk product comprisingthe steps of (a) providing a dairy or dairy substitute blend, (b) addingan emulsifier, (c) thermally processing the dairy or dairy substituteblend, (d) fermenting the blend, (e) admixing a gas with the blend; (f)simultaneously aerating the gas and the dairy or dairy substitute blendto form an aerated product, and (f) cooling the product; and (g)freeze-drying the product.

Yogurt production:

1. Pasteurized lowfat milk is transferred from a tanker truck to largehold tank.

2. All dry ingredients (sugar, gelatin, starch, nonfat dry milk,emulsifier, as well as functional ingredients such as prebiotics) areincorporated into milk via addition to a high shear blender (such asBredo Liqwifier) to achieve homogenous dispersion and initial hydration.

3. Once all dry ingredients have been incorporated, the mixture isagitated for 30 minutes at 35-38 deg F.

4. Following agitation, the mixture is transferred to the HTST plateheat exchanger for thermal processing. The thermal process conditionsused require that all achieve and maintain a minimum temperature of 191deg F at the end of a 4 5 minutes hold time. This temperature and holdtime can vary depending upon the mechanics of the process, for exampleit is possible to go slightly higher in temperature and have a 7 or 8minute hold time.

5. As an optional step for optimizing the formula and the consistency ofaeration, homogenizing of the mixture can occur. The typicalhomogenization pressures are 2000 to 2500 psi at a first stage and200-600 psi at a second stage.

6. After the hold time at 191 deg F., the mix is cooled to 100-112 degF., and transferred to the culturing vat. At this point, the yogurtculture is added (for example, a freeze-dried culture, ABY-2C, suppliedby Danisco Ingredients, or other vendors). The culture is blended withthe pasteurized mix for 30-60 minutes, the mixing is stopped and the vatis maintained at 104-107 deg F. for 4-6 hours. Yogurt is allowed toacidify to pH 4.5 to 4.6, and is then agitated (broken) and cooled to 60deg F. in the culture tank. Final pH will range from is 4.1-4.4.

7. Yogurt is transferred to 250 gal. blending tanks by pumping through acooling press, which lowers temp to 37-45 deg F. Pasteurized fruitpuree, flavors and any desired color will be added. Mixture will beblended with gentle agitation and recirculation for 10-15 minutes.Blended fruit yogurt is transferred to 275 gallon totes.

Production Frozen Yogurt Drops

1. Yogurt will be conveyed/pumped from 275 gallon totes (previouslystored at 34-40 deg F.) to the aerator (in this case, a Mondomixaerator, although other brands exist).

2. Nitrogen gas is admixed to the yogurt via the Mondo mixer (connectedto plant ice water circulation system, to maintain mixing headtemperature at 35-45 deg F.). Product overrun can range from 20% to 80%.However, preferably, the overrun target will be between 30% and 50% andmost preferably between 35% and 45%. This process happens continuously.

3. Aerated yogurt is pumped, maintained at 38-50 deg F., under pressure,to a depositor manifold, where it is distributed to multiple nozzleswhich, via a metering pump, create the appropriately shaped deposit form(in this case, a large chocolate chip shape, although other shapes/formsare possible). The current target shape has a diameter of 13-22 mm(ideal is 15-20 mm), a height of 7-12 mm (ideal is 8-10), and a weightof 0.8-1.3 grams (ideal is 1.0-1.1 g).

4. Drops are deposited onto a solid, stainless steel freezer belt (inthis case, the maker of the belt and freezer is Sandvik).

5. Freezer tunnel air temperature is approximately −20 to −30 deg F.,with high velocity air circulation. Dwell time in the tunnel can rangefrom 3-5 minutes. Frozen pieces exit the tunnel with an internaltemperature of 24-28 deg F.

6. Products are removed from the freezer belt and conveyed to a bulkcase packer, where they are filled into 20-30 lb, plastic bag linedcases. Cases are closed, taped and stored at −20 deg F. until shipmentto OFD.

The following composition of the present invention can be prepared. Thepercentages listed are based on the total weight of the composition.

Example 1

Unflavored yogurt:

Percentage Ingredient by weight Low fat milk 82.89 Non-fat dry milk(NFDM) 4 Sugar 9 Starch/Gelatin Stabilizer Blend 3.7 Yogurt Culture +Skim Milk 0.01 Lactem Emulsifier (Lactic Acid Esters of Monoglycerides)0.4

Example 2

Ingredient % of formula Lowfat Milk 78.442148 NFDM Low Heat 3.68628Sugar, White Satin 8.5068 Starch/Gelatin Stabilizer Blend (0.38% Lactem,3.87532 1.1% Tapioca Starch, 2.3% gelatin Peach Puree, Single Strength,Frozen, Organic 5 Natural Peach Flavor 0.3 Natural Annatto Extract 0.18Yogurt Culture 0.009452 TOTAL 100

Example 3

Ingredient % of formula Lowfat Milk (1.65% fat) 78.442148 NFDM Low Heat3.68628 Sugar, White Satin 8.5068 Starch/Gelatin Stabilizer Blend #17953.87532 Peach Puree, Single Strength, Frozen, Organic 5 Natural PeachFlavor WONF C13206 0.3 Natural Annatto Extract 1211663 0.18 YogurtCulture ABY-2C 0.009452 TOTAL 100

The composition described above is made using the methods describedherein.

It should be appreciated that the present invention is not limited tothe specific embodiments described above, but includes variations,modifications and equivalent embodiments defined by the followingclaims.

1. A freeze-dried, aerated dairy or dairy substitute compositioncomprising: a dairy or dairy substitute ingredient; an emulsifier; and aviscosity enhancer, wherein the dairy composition is pasteurized, has ahardness value from about 0.5 to about 8 pounds of force, and has adissolvability in a range from about 0.1 to about 8 pounds force peakload.
 2. The freeze-dried composition of claim 1, wherein the emulsifieris selected from the group consisting of lactylated mono anddiglycerides, polysorbates, caseinate, whey proteins, egg white protein,and combinations thereof.
 3. The freeze-dried composition of claim 1,wherein the emulsifier is a lactylated mono and diglyceride.
 4. Thefreeze-dried composition of claim 3, wherein the lactylated mono anddi-glycerides are present in an amount of from about 0.001% to about 1%of the composition.
 5. The freeze-dried composition of claim 3, whereinthe lactylated mono and diglyceride is selected from the groupconsisting of lactic acid esters of mono- and di-glycerides, citrateacid esters of mono and diglycerides and distilled monoglycerides. 6.The freeze-dried composition of claim 5, wherein the lactylated mono anddiglyceride is a lactic acid ester of mono glycerides or a blend of monoand diglycerides.
 7. The freeze-dried composition of claim 1 furthercomprising a gelling agent, wherein the gelling agent is gelatin.
 8. Thefreeze-dried composition of claim 1, wherein the dairy or dairysubstitute ingredient is present in an amount of from about 60% to about98% of the composition.
 9. The freeze-dried composition of claim 1,wherein the viscosity enhancer is selected from the group consisting ofstarch, hydrocolloids such as carageenan, guar gum, locust bean gum,pectin, and combinations thereof.
 10. The freeze-dried composition ofclaim 1, wherein the dairy or dairy substitute ingredient is selectedfrom the group consisting of milk, milk powder, yogurt, skim milk, milkproteins, hydrolyzed milk proteins, soy proteins, whey proteins, riceproteins, and combinations thereof.
 11. The freeze-dried composition ofclaim 1 further comprising at least one sugar.
 12. The freeze-driedcomposition of claim 1, wherein the viscosity of the freeze-driedcomposition is from about 1000 to about 500,000 cp.
 13. The freeze-driedcomposition of claim 1 further comprising at least one probiotic.
 14. Afreeze-dried, aerated yogurt composition comprising: a dairy or dairysubstitute ingredient; an emulsifier; and a viscosity enhancer, whereinthe yogurt composition has a hardness value from about 0.5 to about 8pounds of force, and has a dissolvability in a range from about 0.1 toabout 8 pounds force peak load.
 15. The yogurt composition of claim 14,wherein the emulsifier is selected from the group consisting oflactylated mono and diglycerides, polysorbates, caseinate, wheyproteins, egg white protein, and combinations thereof.
 16. The yogurtcomposition of claim 14, wherein the emulsifier is a lactylated mono anddiglyceride.
 17. The yogurt composition of claim 16, wherein thelactylated mono and di-glycerides are present in an amount of from about0.001% to about 1% of the composition.
 18. The yogurt composition ofclaim 16, wherein the lactylated mono and diglyceride is selected fromthe group consisting of lactic acid esters of mono- and di-glycerides,citrate acid esters of mono and diglycerides and distilledmonoglycerides.
 19. The yogurt composition of claim 16, wherein thelactylated mono and diglyceride is a lactic acid ester of monoglycerides or a blend of mono and diglycerides.
 20. The yogurtcomposition of claim 14 further comprising a gelling agent, wherein thegelling agent is gelatin.
 21. The yogurt composition of claim 14,wherein the dairy or dairy substitute ingredient is present in amount offrom about 60% to about 98% of the composition.
 22. The yogurtcomposition of claim 14, wherein the viscosity enhancer is selected fromthe group consisting of starch, hydrocolloids such as carageenan, guargum, locust bean gum, pectin, and combinations thereof.
 23. The yogurtcomposition of claim 14, wherein the dairy or dairy substituteingredient is selected from the group consisting of milk, milk powder,yogurt, skim milk, milk proteins, hydrolyzed milk proteins, soyproteins, whey proteins, rice proteins, and combinations thereof. 24.The yogurt composition of claim 14 further comprising at least onesugar.
 25. The yogurt composition of claim 14, wherein the viscosity ofthe yogurt composition is from about 1000 to about 500,000 cp.
 26. Theyogurt composition of claim 14 further comprising at least oneprobiotic.